The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5. The PCRE library is free, even for building proprietary software.
PCRE homepage: http://pcre.org/

Freeglut, the Free openGL Utility Toolkit, is meant to be a free alter-
native to Mark Kilgard's GLUT library. It is distributed under an X-Consor-
tium style license (see COPYING for details), to offer you a chance to use
and/or modify the source.
It makes use of OpenGL, GLU, and...
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A library containing a ton of useful stuff that really should be in the CLR itself:
Lots of useful extension methods
Some extended collection classes
Some DynamicXML classes
Some serializable Linq classes
An SGML Parser
Some misc Utility classes
Powerful task extensions (works with .NET v4.0 and...
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A library containing a platform abstraction layer that will eventually allow the other ClrPlus libraries to work on something other than Windows.
[Note: This library is not quite ready for public consumption--I'm in the middle of some code reorganization]

A library for manipulating Managed and Native PE binaries:
- digital signing,
- strong naming,
- manifests
[Note: This library is not quite ready for public consumption--I'm in the middle of some code reorganization]

A library containing classes for working with powershell:
- Trivial dynamic powershell invocation from C#
- RESTable cmdlets (so you can host cmdlets via a REST service and call them either remotely or locally)
[Note: This library is not quite ready for public consumption--I'm in the middle of some...
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